Cartridge feeding device



1951 F. M. CARROLL 2,569,798

CARTRIDGE FEEDING DEVICE Filed July 7, 1942 v Sheets-Sheet 1 FIG].

'WgVVENTOR. MONEY 7 Sheets-Sheet 2 F. M. CARROLL CARTRIDGE FEEDING DEVICE IgENTOR. BY ATTORNEY.

Oct. 2, 1951 Filed July 7, 1942 a dot Oct. 2, 1951 F. M. CARROLL CARTRIDGE FEEDING DEVICE 7 Sheets-Sheet 3 Filed July 7, 1942 I NVENOR.

ATTORNEY.

Oct. 2, 1951 F. M. CARROLL 2,569,798

CARTRIDGE FEEDING DEVICE Filed July '7, 1942 7 Sheets-Sheet 4 Oct. 2, 1951 M, CARROLL 2,569,798

CARTRIDGE FEEDING DEVICE Filed July 7, 1942 7 Sheets-Sheet 5 Get 1951 F. M. CARROLL 2,569,798

CARTRIDGE FEEDING DEVICE Filed July '7, 1942 7 Sheets-Sheet 6 Get. 2, 1951 F. M. CARROLL ,7 8

CARTRIDGE FEEDING DEVICE Filed July 7, 1942 7 Sheets-Sheet '7 ATTORNEY.

Patented Oct. 2, 1951 UNITED STATES PATENT OFFICE OARTRID GE FEEDING DEVICE Fred M. Carroll, Binghamton, N. Y., assignor to International Business Machines Corporation, New York, N. Y., a corporation of New York Application July 7, 1942, Serial No. 450,032

Claims.

The purpose of this invention is to afford a constant and certainsupply of ammunition to an automatic gun in action.

The ordinary 30 or 50 calibre machine gun is supplied with ammunition by a belt carrying the rounds in loops. The belt may be stacked in a box or spread out in the open. The action of the average machinegun is, of course, of intermittent character and the belt is advanced by jerks which sometimes, if the belt is laid out straight, may develop such a stress as to jam the gun.

It is a distinct object of this invention to reduce as far as possiblethe stresses incident to the feeding of ammunition to the gun. In accordance with this object the principal part of the ammunition which is being fed toward the gun is kept in motion continuously at a fairly uni-' form rate, only a small number of rounds near the breech of the gun taking part in the intermittent motion characterizing the feed of the rounds into the firing chamber. This object is realized by a mechanism including a regulating and accelerating device, which not only equalizes the continuous feed from the magazine with the intermittent feed into the gun; but also accelerates the small number of rounds nearest the breech of the gun, when the bolt springs forward, to assure the arrival of the next round in ready position, in time to be picked up by the bolt on its next charging movement.

A further object of the invention is to provide an ammunition feeder of the kind described in which the continuous motion of the ammunition toward the gun is derived from a feeding device operated by the intermittent recoil motion of the gun.

A further object is to provide an ammunition feeder of the kind last described, wherein the load imposed upon the gun by the feeder is free from sudden and large variations.

A further object of the invention is to provide an ammunition feeding device which will perform reliably with automatic guns of larger calibre than the ordinary machine gun, such as 20 mm,

guns or larger.

' A still further object of the invention is to provide an ammunition feeding device for an automatic gun which is normally operated by the counter recoil of the gun, but which has a convenient auxiliary operating means for setting it in action, either preparatory to beginning fire, or in the event of a misfire.

Still another object of the invention is to provide a box of ammunition which can be readily placed in position to serve as the magazine of anautomatic gun, with a minimum loss of time. Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a plan view, with parts in section, of a portion of an automatic gun and ammunition feeding means in accordance with the invention assembled therewith.

Fig. 2 is a vertical sectional view through the breech of the gun and a portion of the magazine.

Fig. 3 is a detail elevational view, with parts in section, of portions of the gun and magazine interconnected by a bridge channel comprising a feed regulating mechanism.

Fig. 4 is a vertical transverse section of the magazine, on the line 44 of Fig. 2.

. Fig. 5 is a section on the line 5'5 of Fig. 4.

Fig. 6 is a plan view of the bridge channel comprising the feed regulating mechanism, with a portion of the magazine shown in section.

Figs. 7 and 8 are detail sections on the 1-1 and 8-8, respectively, of Fig. 6.

Fig. 9 is a side elevation of the reeling mechanism, with a portion of the side plate broken away.

Fig. 10 is a vertical section of the reeling mechanism on the line Ill-l 0 of Fig. 11;

Fig. 11 is a vertical section of the reeling mechanism along the axis of the reel shaft.

Fig. 12 is a plan view of the reeling mechanism.

Fig. 13 is a transverse section of the reel.

Fig. 14 is a detail sectional view of the auxiliary reel operating mechanism.

Referring first to Figs. 1 and 2, the invention is shown as applied to a standard 20 mm. automatic gun of the M-2 type. A base plate I is adapted to be mounted on a suitable foundation to provide for training and elevating the gun, the foundationbeing entirely omitted from the drawing. The "drawing shows a portion of the barrel 2 of the gun and a portion of the gun frame 3. The latter is mounted to slide in guides 4 fixed to a bolster block 6 of the base plate I. The gun frame 3 has a longitudinal slot I, into which projects a throat piece 8 fixed upon a slide 5, which has sliding engagement with flanges 3a of the gun frame and is held stationary by means referred to later. The cartridges are fed into this throat piece by means to be described presently, the leading cartridge being held in a ready position by flanges 9 of the throat piece, whence it is moved by the loading mechanism into the flring chamber I0, by the automatic operation of the gun. The loading mechanism does not appear in the drawing. All the structure so far described is that of a standard 20 mm. automatic gun, which is not modified in any respect for th purpose of the present invention.

The ammunition is supplied from a magazine I5, which also constitutes the shipping box. The magazine comprises a casing formed of a bottom plate I6, side plates I1 and I8 (Fig. 4), and two end plates, only the right end plate I9 appearing in the drawing. The casing has bottom flanges 20, 2I and 22 by which it is secured to the base plate I by means of clamps 23. A bracket 41 riveted to the base plate I has ears 4Ia to engage the side of the magazine, to aid in locating it on the base plate. The top of the side plate I1 is bent inward to form a flange I1a, while the top of side plate I8 is bent outward to form a flange I8a. A cover plate comprising an end section II and side section I2 welded together, completes the casing. The end section has a down turned flap Ila, perforated to hook over pins I3 on the side plate I1. The side section I2 of the cover plate rests upon the. flange I 8a and its outer edge has notches I2a which slip under the heads of rivets 24 fixed upon the flange I8a, as the cover is placed in position. The side section I2 is provided with'a hole I4a registering with a hole in the flange I8a, through which a cotter-pin I4 is inserted to secure the cover.

The inner space of the magazine is subdivided by partitions or separators 25 into compartments 26, each wide enough to hold a single stack of cartridges 21. The partitions are secured to the side plates I1 and I8 by machine screws 44-. A flexible feeding device 28, which is shown as a canvas belt, has one end secured at 29 to the end wall I9 of the magazine and is looped down into the successive compartments 26, under the stacks of cartridges contained in them. In packing the magazine, after removing the cover II, I2, the belt 28 is first formed into a small loop extending down into the first compartment 26 at the right, then a cartridge is laid in this loop and pushed down into the compartment far enough to allow a second cartridge to be laid upon it. The cartridges are thus placed in the compartment successively, forcing the belt down further each time, until the compartment is filled, whereupon a second loop is started into the second compartment and the operation repeated. For a reason which will be explained presently there is provided on the top of each partition 25 a row of teeth 30 extending across the width of the belt 28. In packing, the belt is held toward the right clear of these teeth, as shown in Fig. 2, in the compartment containing only two cartridges. The partitions 25 have ribs 3| thereon to guide the cartridges.

Each compartment also contains 4 The jaws 36 are pressed together by a screw 31 to secure the proper degree of friction upon the .retainer 35, so that the latter will hold the cartridges down, until the strong pull of the belt, as described presently, lifts the stack of cartridges in the particular compartment and deflects the retainer to ineffective position. When all the compartments are filled to the level of the tops of the partitions, cartridges are placed in a single layer 38 over the top of the partitions and stacks of cartridges. Then the cover I I, I2 is laid on and secured by the cotter-pin I4. The space in which the top layer of cartridges is held is limited at the top by the flange I1a on the side plate I 1 and the side section I2 of the cover. The space thus enclosed will be seen to constitute a passage 41 communicating in the manner of a header with the compartments 26. The header passage 41 leads to a discharge opening 39 at the end of the magazine nearest the gun. The belt 28 passes from the outer side of the last compartment to the left, over the top of the layer of cartridges 38, and is bent sharply around a curved guide 45 bordering an aperture 44 in the cover section II, to a reeling mechanism indicated generally at 46 in Fig. 1. When the belt is pulled by the reeling mechanism in a manner to be described later, the stack of cartridges in the compartment 26 at the left end of the magazine, in Fig. 2, is first raised, and the cartridges in the passageway 41 are simultaneously pressed to the right through the opening 39. The teeth 36 on the partition at the right side of the left end a spring 32 comprising a plurality of leaves threaded upon a wire 33 so as to move freely up and down. The spring is positioned under the bullet end 34 of the cartridges and is pressed compartment 26 prevent the belt from slipping over the top of this partition, thereby confining the feeding action for the moment to the single stack of cartridges at the left end of the magazine. When theflrst compartment is empty, the belt pulls away from the teeth 30 at the top of the partition forming the right side of the compartment just emptied, and the pull is thereupon transferred to the cartridges in the next compartment to the right. The stacks of cartridges are thus fed one by one into and through the passageway 41, until the magazine is empty.

The ammunition fed out of the magazine by the belt 28 passes to the gun through a bridge channel indicated generally at 48 in Fig. 2. This bridge channel serves not only to guide the ammunition to the gun, but also be regulate the feed,'and toaccelerate a small group of cartridges nearest the gun, each time the loading mechanism operates, to place another cartridge in ready position at the breech immediately, without dependence upon the rate at which the ammunition is moving from the magazine toward the gun. The movement of the cartridges from the throat 8 into the firing chamber I0 is intermittent. The considerable weight of the cartridges in process of movement from the magazine toward the gun at any particular time would ofier large resistance to the sudden acceleration which would be necessary, if their feed were to conform to the intermittent operation of the loading mechanism. Furthermore, if it were necessary to accelerate all of the cartridges moving toward the gun, in order to move the penultimate round to ready position, the retarding force might be so great as to cause said round to arrive late and jam the gun. To eliminate the necessity for setting all of these cartridges in motion at each operation of the breech mechanism, the bridge channel is provided with the regulating and accelerating mechanism previously mentioned,

which enables the line of cartridges moved to- "its" inner position. These tongues enter recesses ward the gun to continue in motion during the intervals between feed of the cartridges into the firing chamber, and accelerates the last few" rounds toward the breech independently of the rest of the rounds.

The throat 8 of the is formed with two cheeks 58 and (Fig. 6) between which a mouth piece 52 is fixed by screws 53. Since the throat 8 has a sliding connection with the gun frame 3, means are provided to hold it against longitudinal movement. For this purpose the bracket 4| riveted to the base plate I has a lug 42 which engages in a notch 52a of the mouth piece 52. When the magazine is clamped in position on the base plate I, the aperture of the mouthpiece 58 registers with the opening 38 at the right end of the passageway 41. Between the mouth piece 82' and the throat 8 is a rocking regulator element, or accelerator, indicated generally at 55 in Fig. 2. The rocking member comprises a bottom plate 56, two end plates 51 and 58 and a top plate 58 secured to the end plates by screws 88. The end plates 51 and 58 are pivoted to the cheeks 58 and 5I by pins 54, which determine the rocking axis of the accelerator. The top plate 58 has fixed to it guide tongues 5| and 82, the

former being adapted to guide the shell end of the cartridges, while the latter guides the bullet end, which accounts for their slight difference in shape and position (see Figs. 7 and 8) The top plate 58 also has two ears 65 to whichare attached springs 88 anchored at their opposite ends to pins 81 on the throat 8. The accelerator is thus biased in a clockwise direction, so that downwardly extending lips 63 on the right edge of its bottom plate 58 rest upon a shoulder 88 of the throat 8.

It will be observed that the rocking of the accelerator in counterclockwise direction will in- 1 crease the length of the path through which the cartridges travel to the throat. The accelerator rocks in response to the feeding pressure of the cartridges and thus equalizes the substantially continuous feed of the cartridges from the magazine, with the intermittent feed of the cartridges from the throat 8 into the firing chamber I8 of the gun. When the bottom round in the throat 8 is pushed forward by the bolt into the firing chamber, the accelerator, which has rocked out ward in the,interval between loading operations, snaps the next few cartridges downward with a speed considerably greater than that of the cartridges moving from the magazine. .The'feed of the next round to ready Position is thus effected by means operating uniformly and independently of the general movement of ammunition from the magazine. In all positions of the accelerator the cartridges are held in a single line and jamming is thereby avoided. Guide tongues are provided at 18 on the mouth piece 52 to bridge the gap between the mouth piece and the top plate 58 of the rocking member, when the latter is in II in the top plate 58 as the regulating member rocks to its outer position. Additional guides are placed at 12 and 13 on the throat 8, to direct the cartridges down into the throat when the regulator is in its outer position (see Fig. 2). Tongues 18 on the throat 8 serve to complete the guiding surface at the left side of the throat when the regulator is in its outer position.

The reeling mechanism is mounted in two side plates 88 and M (Figs. 9 to 12) secured by bolts 82 to the base plate I. A stationary shaft 83 is secured by hubs 84 and 85 to the side plates 88 and BI, respectively, and a sleeve as is journaled by roller bearings 81 upon the shaft 83. A reel 88, joumaled by its hub 88 upon the sleeve 88, has flanges 88, 8I secured to the rim 82 of the reel by screws 83. At the right side of the flange 88 there is mounted upon the sleeve 88 a ratchet disk 85. This disk is keyed to the sleeve 88 by keys 86 engaging in slots of the disk and in key slots 81 of the sleeve 86. Between the ratchet disk 85 and the flange 88 is a felt friction disk 88. Outside of the disk 85 the sleeve 88 has a flange 88. At the left side of the flange 8| a disk I88 is mounted upon the sleeve 88. This disk is also keyed. to the sleeve 85 by keys I8I' held in slots I82 of the disk I 88 (see Fig. 10). Between the disk I88 and the flange 8I of the reel there is a rubber disk I88, a metal washer I88 and-a felt disk II 8. A collar I83 isinterposed between the disk I88 and a nut I84 engaging threads I85 of the sleeve 85 and having wrench sockets I88. By screwing the nut I84 toward the flange-88 the entire assembly on the sleeve 86 is squeezed together, thereby forming a friction connection between the disks 85 and I88 and the flanges 88 and 8| of the reel. As shown in Fig. 13, the rim 82 of the-reel has a recess I I5 in which stands a pin I I8, around which the belt 28 can be looped to secure it to the reel. The belt is passed under the pin H5 and the end of the belt is then laid in a first layer II1 around the rim 82, so that the second layer II8 will bind upon it.

Means are provided to rotate the disk 85 in a ter .recoil motion of the gun. A ratchet plate I28 revolubly mounted by its hub II8 on the shaft 83, carries a pair of pawls I2I and I22 biased by springs I23 against the ratchet teeth of the disk 85. The pawlsare spaced from each other around the periphery of the disk 85 by a whole number of teeth plus one-rhalf tooth so that one or the other will. engage a tooth of the ratchet wheel. A tubular connecting rod I25 is pivotally connected by a pin I26 to the ratchet plate I28 and its opposite end is formed with a loop I21 engaging a pin I28 on the breech block 3 of the gun. A collar I28 resting against a shoulder I38 of the connecting rod I25 has hooked into it one end of a heavy spring I3I, the other end of which is anchored to thebase plate I at a point which does not appear in the drawing. Upon recoil of the gun, the spring I3I pullsthe connecting rod I25 back, the elongated openin in loop I21 relieving the connecting rod of the shock of the recoil. When the connecting rod reaches its back limit position, one or the other of the pawls I2I, I22 engages a tooth of the ratchet disk I85 and the counter recoil motion of the gun thrusts the connecting rod forward, turning the disk 85 counterclockwise. The motion is transmitted through the friction connection previously described, to the reel.

Retrograde motion of the reel is prevented by means associated with the left flange 8I. A ratchet ring I35 is mounted upon the flange 8I by rivets I35 and spacing washers I31. Two

retrograde pawls I38, I38 are pivoted upon a aseavos 1 arm I40. A spring I50 normally holds the piston at the lower end of the cylinder I45, a screw I5I in the head of the connecting rod I48 abutting upon the floor of the cylinder I45 to stop the arm I40. A screw threadedport I52 in the cylinder I45 provides means for connecting to the cylinder, a pipe leading to a source of hydraulic pressure. Thus, the ratchet arm I40 serves as an auxiliary operator for the reel, to be used in starting the winding of the reel, or in continuing the winding upon failure of recoil due to a misflre. The reel can also be turned manually by inserting a bar in a socket I53 (Fig. 12) in the hub H9.

The winding of the reel by the ratchet mechanism is intermittent, but the pull on the, belt should be continuous. For this reason the belt is looped over an idler pulley I55 mounted on a rocking frame I56 pivoted on a bolt I5I' secured to the side plates of the reel mechanism. At the knee of the rocking frame I56 there is a cross bar I58, upon which the ends of two heavy springs I59 are hooked. These springs are anchored to pins I60 on the side walls 80 and 8I. The motion of the frame I56 is limited by two links I 6| pivoted on the pin I56 and slotted at I62 to embrace pins I63 upon the side plates 80 and BI. Idler pulley I 55 and its rocking frame yield to the tension of the belt, to equalize the tension during intervals between the feedin movements of the ratchet mechanism. The load of the feeding mechanism upon the gun is fairly uniform, at least free from violent fluctuation.

Means are provided to disengage thepawls I2I and I22 and also the pawls I38 and I39, so that the reel can be unwound when the magazine has been emptied. For this purpose there is mounted on a round bar I65 extending between the plates 80 and 8|, a rocking frame'comprising an arm I66 engageable with the tails of the pawls I38 and I39, an arm I61 engageable with the tails of the pawls I2I and I22, and a hub I68 rigidly connecting the arms I66 and I61. Movement of the rocking frame is limited by a pin I69 riveted on the side plate 8| and extending into a hole I of larger diameter in the arm I611 A coil spring I 'II has one end biased against the pin I68 and the other against the arm I 61, to hold the rocking frame normally out of contact with the pawls. A handle I'I2 on the arm I66 can be pressed toward the reel to move both arms I66 and I61 against their pawls, to release the reel for reverse rotation.

, each time a cartridge is fed into the firing cham ber of the gun.

2. The combination with an automatic gun having a throat at its breech from which the cartridges are withdrawn intermittently by the automatic operation of the gun, of a cartridge feeding means comprising a guideway terminating at said throat, feeding means for pressing the cartridges continuously through said guideway toward said throat, said guideway being formed, in part, by a guiding and regulating portion near said throat movable in response to the feeding pressure of the cartridges in contact therewith, in a direction to elongate the path of the cartridges through said guideway, and resilient means continuously exerting aforce upon said guiding and regulating portion, tending to resist the movement of said portion in said direction.

3. The combination with an automatic gun having a throat from which cartridges are intermittently fed into the firing chamber of the gun, of a magazine comprising means to guide a series of cartridges to the throat of the gun sideways in a single file, feed means comprising an impelling device adapted to press the cartridges through said guide means, operating means for said impelling device comprising a ratchet drive mechanism operatively connected to said impelling device, and means whereby said :movably mounted so as to yield in response to the pressure of the cartridges therein, in a direc- While there have been shown and described having a throat from which cartridges are inter-' mittently fed into the firing chamber of the gun,

of a magazine comprising means to guide a: series of cartridges to the throat of the gun sideways in single file, said guide means including a curved section adjacent the throat of the gun pivoted on a transverse axis so as to be movable toward the throat of the gun to reduce the length of the path defined by said guide t s tion to expand the capacity of said guide means near said throat, and resilient means constantly exerting a force on said movable section tending to resist the movement thereof in said direction.

4. The combination with an automatic gun having means to hold a cartridge in ready position to be moved into the firing chamber by the loading mechanism of the gun, of means to guide cartridges sideways in single file to said holding means, feed means to press a succession of carridges continuously through said guide means to said holding means, said guide means including a curved section near said holding means having a telescopic relation to an adjacent section of said guide means, said curved section being movable in response to the pressure of the cartridges to elongate said guide means while maintaining a continuous passageway therethrough, and spring meam opposing said movement of said curved section.

5. The combination with an automatic gun having means to hold a cartridge in ready position to be moved into the firing chamber by the loading mechanism of the gun, of a magazine comprising means to guide a disconnected series of mutually abutting cartridges sideways in single file to said holding means, a main i'eed means 5 adapted to exert a force on a cartridge of said series remote from said holding means, in a direction to press the cartridges or said series between said remote cartridge and said holding means through said guide means toward said holding means and with said force thereby applied to the leading cartridge of said series, and by the transmission of the force through the mutually abutting surfaces of the cartridges of said series between said remote cartridge and said holding means, and auxiliary means mounted adiacent the holding means for continuously applyin an additional force to a small number of the cartridges in said guide meansnearest said holding means tending to push them toward Said holding means.

FRED M. CARROLL.

REFERENCES CITED The following references are of record in the flle of this patent:

10 UNITED sums m'rem's Number Number Name Date Bjerkness Feb. 8, 1887 Langdon June 2, 1908 Vollmer Apr. 25, 1922 Fritz July 17, 1923 Russell et a1 Aug. 12, 1924 Dabrasky Jan. 26, 1932 Reising Aug. 2, 1932 Capell May 2, 1933 Kobe Sept. 20, 1938 Hertel Aug. 14, 1945 Burgess Feb. 11, 1947 FOREIGN PATENTS Country Date Austria Jan. 10, 1920 Germany Nov. 24, 1936 France 1 June 17, 1930 France Mar. 8, 1937 France Feb. 8, 1938 Great Britain Jun; 20, 1938 Great Britain May 30, 1941 

